package com.ea.admin.utils;

import com.alibaba.excel.enums.CellDataTypeEnum;
import com.alibaba.excel.metadata.CellData;
import com.alibaba.excel.metadata.Head;
import com.alibaba.excel.util.CollectionUtils;
import com.alibaba.excel.write.metadata.holder.WriteSheetHolder;
import com.alibaba.excel.write.style.column.AbstractColumnWidthStyleStrategy;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.util.CellRangeAddress;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class CustomCellWriteWeightConfig extends AbstractColumnWidthStyleStrategy {
    private final Map<Integer, Map<Integer, Integer>> CACHE = new HashMap<>();

    private static boolean isMergedRegion(WriteSheetHolder writeSheetHolder, Cell cell) {
        boolean isMergedRegion = false;
        Sheet sheet = writeSheetHolder.getSheet(); // 获取Sheet对象
        int rowIndex = cell.getRowIndex(); // 单元格所在行索引
        int colIndex = cell.getColumnIndex(); // 单元格所在列索引

        List<CellRangeAddress> mergedRegions = sheet.getMergedRegions();
        for (CellRangeAddress mergedRegion : mergedRegions) {
            if (rowIndex >= mergedRegion.getFirstRow() && rowIndex <= mergedRegion.getLastRow()
                    && colIndex >= mergedRegion.getFirstColumn() && colIndex <= mergedRegion.getLastColumn()) {
                // 当前单元格在合并单元格区域内
                isMergedRegion = true;
                break;
            }
        }
        return isMergedRegion;
    }

    @Override
    protected void setColumnWidth(WriteSheetHolder writeSheetHolder, List<CellData> cellDataList, Cell cell, Head head, Integer integer, Boolean isHead) {
        boolean needSetWidth = isHead || !CollectionUtils.isEmpty(cellDataList);
        boolean isMergedRegion = isMergedRegion(writeSheetHolder, cell);

        if (needSetWidth && !isMergedRegion) {
            Map<Integer, Integer> maxColumnWidthMap = CACHE.computeIfAbsent(writeSheetHolder.getSheetNo(), k -> new HashMap<>());

            Integer columnWidth = this.dataLength(cellDataList, cell, isHead);
            if (columnWidth >= 0) {
                if (columnWidth > 254) {
                    columnWidth = 254;
                }

                Integer maxColumnWidth = maxColumnWidthMap.get(cell.getColumnIndex());
                if (maxColumnWidth == null || columnWidth > maxColumnWidth) {
                    maxColumnWidthMap.put(cell.getColumnIndex(), columnWidth);
                    Sheet sheet = writeSheetHolder.getSheet();
                    sheet.setColumnWidth(cell.getColumnIndex(), columnWidth * 256);
                }

            }
        }
    }

    /**
     * 计算长度
     */
    private Integer dataLength(List<CellData> cellDataList, Cell cell, Boolean isHead) {
        if (isHead) {
            return cell.getStringCellValue().getBytes().length;
        } else {
            CellData cellData = cellDataList.get(0);
            CellDataTypeEnum type = cellData.getType();
            cellData.setType(CellDataTypeEnum.STRING);
            if (type == null) {
                return -1;
            } else {
                switch (type) {
                    case STRING:
                        // 换行符（数据需要提前解析好）
                        int index = cellData.getStringValue().indexOf("\n");
                        return index != -1 ?
                                cellData.getStringValue().substring(0, index).getBytes().length + 1 : cellData.getStringValue().getBytes().length + 1;
                    case BOOLEAN:
                        return cellData.getBooleanValue().toString().getBytes().length;
                    case NUMBER:
                        return cellData.getNumberValue().toString().getBytes().length;
                    default:
                        return -1;
                }
            }
        }
    }
}
